Al-Umar et al. Geoenvironmental Disasters (2020) 7:9 Geoenvironmental Disasters https://doi.org/10.1186/s40677-020-0142-8 RESEARCH Open Access GIS-based modeling of snowmelt-induced landslide susceptibility of sensitive marine clays Mohammad Al-Umar1, Mamadou Fall1* and Bahram Daneshfar2 Abstract In this study, a simulation tool, based on the combination of Geographic Information System (GIS) and Grid-Based Regional Slope-Stability Model (TRIGRS), is developed to assess and predict the snowmelt-induced landslides in areas of sensitive marine clays in the Ottawa region (Canada). Topographic, geologic, hydrologic, and geotechnical information of the study area, in addition to snowmelt intensity data for different periods, was required to conduct this modeling study. Snowmelt intensity records for periods of 6–48 h, 3–15 days, 25 days, and 30 days, as well as the information on historical landslides in the study area, were used to examine both the timing and location of shallow landslides due to snowmelt across the Ottawa region. The developed tool is validated by comparing the predicted landslide-susceptible areas with the historical landslide maps in the study area. A good agreement between the predicted and recorded historical landslides was obtained, which suggests that the developed GIS- TRIGRS based tool can predict relatively well the snowmelt-induced landslide susceptibility in the sensitive marine clays. The modeling results show that high slope areas of sensitive marine clays are more prone to snowmelt- induced landslides. As a result, this simulation tool could be used to assess and/or predict snowmelt-induced landslides in different areas of the Ottawa region, which is an important means for decision-making processes with respect to protecting the population and infrastructure against snow-melt induced marine clay landslides. Keywords: Sensitive marine clay, Snowmelt, GIS, TRIGRS, Landslide, Soil slope stability, Modeling Introduction 12,000 years, are considered to be young glacial deposits There are many types of soils that cause geotechnical (Haché et al. 2015; Taha, 2010). problems and geoenvironmental hazards or disasters. Several landslides have previously occurred in these Sensitive marine clay is one of these soils; they will sig- soils and in many countries as reported in many studies nificantly lose their shear strength if their structure is (e.g., L'Heureux 2013; Aylsworth et al. 1997). For in- disturbed. During the last glacial era, glaciers covered stance, numerous landslides have occurred in the Can- many areas of the world, especially in the northern re- adian sensitive marine clay formations, particularly in gions of the earth (e.g, Alaska, Canada, Sweden, and the Ottawa region. A key trigger of these landslides has Norway). These areas are found to contain these prob- been identified as snow melting in the spring (Quinn lematic soils (Theenathayarl 2015). The provinces of 2009). During the snowmelt in the spring, huge quan- Quebec and Ontario (particularly in the Ottawa region) tities of snowmelt water is released, which has a negative in Canada have sensitive marine clays (locally called effect on the stability of the slopes. Leda clay or Champlain sea clay), which cover relatively As the population of the Ottawa region is steadily ris- large areas. These Canadian marine clays, younger than ing (currently at approximately 900,000) (City of Ottawa 2015) there is a continuous growth in infrastructure fa- cilities, including residential and other buildings, trans- * Correspondence: [email protected] portation infrastructure, and utilities located on the 1Department of Civil Engineering, University of Ottawa, 161 Colonel by, problematic marine clay. However, the presence of sen- Ottawa, Ontario K1N 6N5, Canada sitive clay slopes in the Ottawa region and presence of Full list of author information is available at the end of the article © The Author(s). 2020 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Al-Umar et al. Geoenvironmental Disasters (2020) 7:9 Page 2 of 18 snowmelt in the spring, poses a landslide hazard for and (iii) deterministic approaches (Pathak 2016; Quinn both the population and infrastructure (Nader et al. 2009; Fall et al. 2006; Van Westen et al. 1997). The ad- 2015; Taha, 2010; Quinn 2009). A good engineering vantages and disadvantages of each technique have been practice to reduce this landslide hazard and potential outlined in numerous publications (e.g. Fall et al. 2006; impact on people and infrastructure is to identify or as- Dai and Lee 2001). Moreover, landslide susceptibility sess the sensitive marine slopes that are susceptible to mapping in large areas usually involves the handling, snowmelt-induced landslides as well as develop a tool processing, and interpretation of a large amount of geo- that can assess and predict these snowmelt-induced spatial data. Therefore, during the past decades, the landslides in Ottawa sensitive marine clays. Indeed, land- Geographical Information System (GIS) has been suc- slide susceptibility mapping is an important tool for cessfully used in several studies (Zhang and Wang 2019; decision-making processes with respect to protecting the Chen et al. 2015; Mukhlisin et al. 2010; Quinn 2009; population and infrastructure against marine clay land- Thapa and Esaki 2007; Fall et al. 2006; Chang slides (Nader et al. 2015). However, until now, no tool et al., 1999) to conduct landslide susceptibility assess- has been developed to assess and map the sensitive clays ment and mapping. Additionally, the infinite slope sta- slopes in Ottawa that are susceptible to landslides in- bility model has also been merged with GIS to assess duced by snowmelt. This knowledge and technology gap shallow landslide potential and the distribution of the is addressed in the present study. factor of safety in a specified region (e.g., Sorooshian It should be emphasized that studies on snowmelt- et al. 2015; Quinn 2009; Fall, 2006; Van Westen et al. induced landslides are rare compared to rainfall-induced 1997). Furthermore, Transient Rainfall Infiltration and landslides. For instance, in the Clearwater River Basin in Grid-based Regional Slope-stability (TRIGRS) (Baum Central Idaho, Gorsevski et al. (2000) used a Digital Ele- et al. 2008), a deterministic, spatially distributed model vation Model (DEM) to derive analyses of snowmelt and that combines a hydrologic 1-D transient infiltration rainfall triggered landslides on a small watershed named model (Iverson 2000) and an infinite slope stability Rocky Point. Kimura et al. (2014) used a probabilistic model to calculate the factor of safety with respect to approach to estimate landslide hazard. According to the time and location, have been successfully applied in sev- topography for the study area, GIS analysis was used to eral studies for modeling the timing and spatial distribu- classify these landslides into three groups. Khezri et al. tions of shallow landslides and to compute their factor (2013) used a GIS system to predict landslide suscepti- of safety with respect to time and location (e.g. Raia bility in the central Zabbasin of the West-Azerbaijan et al., 2014; Park et al. 2013; Salciarini et al. 2008). The province in Iran. This study, claims that the key factor TRIGRS model, when used for either saturated or unsat- of mass movement is the sudden melting of snow as a urated soils, is appropriate for shallow landslide suscep- result of the presence of water in the soil, increasing the tibility analysis (Raia et al., 2014). The application of pore water pressure and hydrostatic level. Kawagoe et al. models like TRIGRS in a GIS environment for landslide (2009) analyzed snowmelt’s effect on landslide occur- susceptibility evaluation requires digital spatial topo- rence by using a probabilistic model based on multiple graphic, geologic, and hydrologic data in addition to any logistic regression analysis. The analysis was executed by previous snowmelt and rainfall-induced landslide ac- using a logistic regression model to produce landslide counts, which are fundamental to test the model results susceptibility maps across Japan. The results revealed (Baum et al. 2008; Baum et al. 2002). that across Western Japan (throughout the mountain Based on the facts mentioned above, in this work, the ranges near the Japan Sea), there exists a 95% landslide TRIGRS model combined with GIS will be applied to probability. Ayalew et al. (2004) created a landslide sus- the study area to assess snowmelt induced landslides, ceptibility map near the Agano River in Tsugawa using a and to develop snowmelt induced susceptibility landslide GIS based analysis of the spatial database collected for maps. This study aims to develop a GIS-TRIGRS model 791 landslides. Most often, landslides were triggered by or tool and map to assess the shallow and snowmelt- heavy amounts of snow and rainfall. However, no studies induced landslide susceptibility in sensitive marine clays on snowmelt induced landslides in the sensitive marine in Ottawa. clays in the Ottawa have been conducted, and there is no tool to assess or predict the snowmelt-induced land- Study area slide susceptibility for the Ottawa region. The Ottawa region (Fig. 1) is located between the latitudes Several approaches have been established to evaluate of 45.00–45.50 N and the longitudes 75.50–76.00 W. It is landslide susceptibility and identify the potential of un- bounded to the north by the Ottawa River. It is also a re- stable slopes/regions. Such approaches can be divided gion consisting of gentle slopes ranging from 0 to 33 de- into three key groups: (i) expert evaluation (i.e. inven- grees; although, Western and Northern Ottawa maintain tory, heuristic approaches), (ii) statistical approaches, higher slopes.